Air spring devices, also referred to as air springs for short, which are clamped between the running gear and the body and have an air spring bellows which, in turn, is secured between the air spring components comprising the air spring cover and the air spring piston, are known in a large number of embodiments. In operation, the air spring is under an internal excess pressure. Under load and in the case of springing movements, the air spring bellows rolls on the outer contour of at least one air spring piston, forming a rolling fold. An air spring of this kind is often used in road or rail vehicles in order to achieve comfortable springing.
In this context, there are both air springs on which the air spring bellows forms a rolling fold on only one side, namely in general on the air spring piston, and air springs on which the air spring bellows is clamped between the air spring cover and the air spring piston and forms a (rolling) fold on both sides.
To secure the end region of the air spring bellows on the air spring cover, use is generally made of clamping rings which can be deformed elastically in a radial direction and which clamp the end region of the air spring bellows positively and frictionally on the clamping section of the air spring cover.
However, the internal excess pressure and the resulting forces in the working chamber of the air spring mean that the clamped joint between the air spring bellows and the air spring cover and/or air spring piston is subject to high loads, with the result that there is the risk that the end of the air spring bellows will be pulled out of the clamped joint, i.e. from under the clamping ring. Moreover, the leaktightness in the clamping region decreases especially when there are large temperature fluctuations.
Radial force components furthermore ensure that the bellows pressure is reduced since the air spring bellows produces an expansion of the clamping ring when subjected to pressure.
A large number of fastening variants is known for the purpose of securing the air spring bellows on one of the air spring components. For example, DE 100 50 777 A1, which is incorporated by reference, describes an air spring having a convex-shaped clamping region of the air spring cover, on which a concave-shaped clamping ring is press-fitted. However, it has been found that the problems described can only be solved to a limited extent in the case of the known clamped joints.